124317-09-5Relevant articles and documents
PROCESS FOR PRODUCING PHOSPHONIUM BORATE COMPOUND, NOVEL PHOSPHONIUM BORATE COMPOUND, AND METHOD OF USING THE SAME
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Page/Page column 60, (2008/06/13)
The invention relates to a phosphonium borate compound represented by Formula (I) (hereinafter, the compound (I)). The invention has objects of providing (A) a novel process whereby the compound is produced safely on an industrial scale, by simple reaction operations and in a high yield; (B) a novel compound that is easily handled; and (C) novel use as catalyst. ????????Formula (I) : (R1)(R2)(R3)PH·BAr4?????(I) wherein R1, R2, R3 and Ar are as defined in the specification. The process (A) includes reacting a phosphine with a) HCl or b) H2SO4 to produce a) a hydrochloride or b) a sulfate; and reacting the salt with a tetraarylborate compound. The compound (B) has for example a secondary or tertiary alkyl group as R1 and is easily handled in air without special attention. The use (C) is characterized in that the compound (I) is used instead of an unstable phosphine compound of a transition metal complex catalyst for catalyzing C-C bond, C-N bond and C-O bond forming reactions and the compound produces an effect that is equal to that achieved by the transition metal complex catalyst.
A versatile catalyst for heck reactions of aryl chlorides and aryl bromides under mild conditions
Littke,Fu
, p. 6989 - 7000 (2007/10/03)
In the presence of Cy2NMe, Pd/P(t-Bu)3 serves as an exceptionally mild and versatile catalyst for Heck reactions of aryl chlorides and bromides. A sterically and electronically diverse array of aryl bromides, as well as activated aryl chlorides, couple with a range of mono- and disubstituted olefins at room temperature, furnishing the arylated product with high E/Z stereoselection. The corresponding reactions of a broad spectrum of electron-neutral and electron-rich aryl chlorides proceed at elevated temperature, also with high selectivity. In terms of scope and mildness, Pd/P(t-Bu)3/Cy2NMe represents an advance over previously reported catalysts for these Heck coupling processes.
Potential Antisecretory Antidiarrheals. 2. α2-Adrenergic 2-imidazolines
Moormann, Alan E.,Pitzele, Barnett S.,Jones, P. H.,Gullikson, Gary W.,Albin, David,et al.
, p. 614 - 626 (2007/10/02)
Lofexidine, an α2-agonist, has central hypotensive activity and peripheral intestinal antisecretory activity.Analogues were synthetsized with increased polarity in an attempt to prevent penetration of the blood-brain barrier.The compounds were evaluated in the cholera toxin treated ligated jejunum of the rat and in the Ussing chamber with a rabbit ileum preparation.Active compounds were determined to be α2-adrenergic agonists by yohimbine reversals of their Ussing chamber activities.The 2,6-dimethyl derivative of lofexidine, 4a, was as active as lofexidine invivo, but derivatives with 2,6-substituents larger than ethyl were inactive. (Aryloxy)alkyl derivatives which have an imidazoline and a methyl or larger group as part of the alkyl exhibited the best antisecretory activity.Compounds with substituents in the para position of the phenyl ring were generally inactive. 3-Amino-2,6-dimethyl derivative 21 was twice as active as 4a.A 2-methyl substituent is required in the 3-amino series to retain good activity. 2-methyl derivative 12a had activity comparable to that of 4a, while 6-methyl derivative 12f was inactive.Substituents on the 3-amino group did not affect the activity, but substituting a hydroxyl for the amino group produced an inactive compounds.Replacing the phenyl moiety with a 4-indole resulted in retention of activity, but other heterocycles were inactive.Compound 12a was resolved and d isomer 32 was five times more potent than l isomer 33.The more active compounds in the rat cholera toxin assey (RCTA), when evaluated in the dog, exhibited antisecretory activity but also exhibited centaral nervous system (CNS) effects, sedation and ataxia, at 10 mg/kg, and in spontaneouslyhypertensive rats at 50 mg/kg.A measure of polarity, log P, was calculated for the (aryloxy)alkyl groups.Regression analysis showed no correlation of antisecretory ED50 to the calculated log P.The active compounds did not show a separation of the central CNS effects from the peripheral antisecretory activity by increasing the polarity.
